LibWeb: Move Timer from DOM directory & namespace to HTML

Timers are part of the HTML spec. :^)
https://html.spec.whatwg.org/multipage/timers-and-user-prompts.html#timers

Userland/Libraries/LibWeb/HTML/Timer.cpp

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibCore/Timer.h>
+#include <LibWeb/HTML/Timer.h>
+#include <LibWeb/HTML/Window.h>
+
+namespace Web::HTML {
+
+NonnullRefPtr<Timer> Timer::create(Window& window, i32 milliseconds, Function<void()> callback, i32 id)
+{
+    return adopt_ref(*new Timer(window, milliseconds, move(callback), id));
+}
+
+Timer::Timer(Window& window, i32 milliseconds, Function<void()> callback, i32 id)
+    : m_window(window)
+    , m_id(id)
+{
+    m_timer = Core::Timer::create_single_shot(milliseconds, [this, callback = move(callback)] {
+        NonnullRefPtr strong_timer { *this };
+        callback();
+    });
+}
+
+Timer::~Timer()
+{
+    m_window.deallocate_timer_id({}, m_id);
+}
+
+void Timer::start()
+{
+    m_timer->start();
+}
+
+}

Userland/Libraries/LibWeb/HTML/Timer.h

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Forward.h>
+#include <AK/Function.h>
+#include <LibCore/Forward.h>
+#include <LibWeb/Forward.h>
+
+namespace Web::HTML {
+
+class Timer final : public RefCounted<Timer> {
+public:
+    static NonnullRefPtr<Timer> create(Window& window, i32 milliseconds, Function<void()> callback, i32 id);
+    ~Timer();
+
+    void start();
+
+private:
+    Timer(Window& window, i32 milliseconds, Function<void()> callback, i32 id);
+
+    RefPtr<Core::Timer> m_timer;
+    Window& m_window;
+    i32 m_id { 0 };
+};
+
+}

Userland/Libraries/LibWeb/HTML/Window.cpp

@@ -15,7 +15,6 @@
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/DOM/Event.h>
 #include <LibWeb/DOM/EventDispatcher.h>
-#include <LibWeb/DOM/Timer.h>
 #include <LibWeb/HTML/BrowsingContext.h>
 #include <LibWeb/HTML/EventLoop/EventLoop.h>
 #include <LibWeb/HTML/MessageEvent.h>
@@ -23,6 +22,7 @@
 #include <LibWeb/HTML/Scripting/ClassicScript.h>
 #include <LibWeb/HTML/Scripting/ExceptionReporter.h>
 #include <LibWeb/HTML/Storage.h>
+#include <LibWeb/HTML/Timer.h>
 #include <LibWeb/HTML/Window.h>
 #include <LibWeb/HighResolutionTime/Performance.h>
 #include <LibWeb/Layout/InitialContainingBlock.h>
@@ -174,7 +174,7 @@ void Window::clear_interval(i32 id)
     m_timers.remove(id);
 }
 
-void Window::deallocate_timer_id(Badge<DOM::Timer>, i32 id)
+void Window::deallocate_timer_id(Badge<Timer>, i32 id)
 {
     m_timer_id_allocator.deallocate(id);
 }
@@ -262,7 +262,7 @@ i32 Window::run_timer_initialization_steps(Bindings::TimerHandler handler, i32 t
     };
 
     // 13. Run steps after a timeout given global, "setTimeout/setInterval", timeout, completionStep, and id.
-    auto timer = DOM::Timer::create(*this, timeout, move(completion_step), id);
+    auto timer = Timer::create(*this, timeout, move(completion_step), id);
     m_timers.set(id, timer);
     timer->start();
 

Userland/Libraries/LibWeb/HTML/Window.h

@@ -76,7 +76,7 @@ public:
 
     void set_wrapper(Badge<Bindings::WindowObject>, Bindings::WindowObject&);
 
-    void deallocate_timer_id(Badge<DOM::Timer>, i32);
+    void deallocate_timer_id(Badge<Timer>, i32);
 
     HighResolutionTime::Performance& performance() { return *m_performance; }
 
@@ -127,7 +127,7 @@ private:
     WeakPtr<Bindings::WindowObject> m_wrapper;
 
     IDAllocator m_timer_id_allocator;
-    HashMap<int, NonnullRefPtr<DOM::Timer>> m_timers;
+    HashMap<int, NonnullRefPtr<Timer>> m_timers;
 
     NonnullOwnPtr<HighResolutionTime::Performance> m_performance;
     NonnullRefPtr<Crypto::Crypto> m_crypto;